A web directory is a directory of World Wide Web. Additionally, it is the collection of high PR websites which are arranged in different categories and subcategories. The process of submitting your website link to the web directory is called Directory Submission.
Additionally, it helps to bring high-quality back links for your site which increases site ranking.
So if you want to get back links for your site then you have to submit your website or blog in web directory in suitable category or subcategory with some details.